地质历史时期生物多样性统计中的偏差是普遍存在的。文中以奥陶纪海洋生物和二叠纪腕足动物分异度为例介绍和讨论古生物多样性统计中的偏差问题。认为在研究某些时段分异度时不能依靠单一的种、属或科的数量来建立分异度模式，而需要用生物分异度、灭绝率和新生率等多种计算方法来综合分析。同时古生物分异度的研究受到化石记录的完整性、研究、保存和采集程度、时间段的不均一性等多种因素影响，因此，大多需要应用稀疏标准化法等对不同时段或化石群在同等量化标准的基础上进行比较和校正后，才能得到比较符合实际的分异度模式。

Sampling biases have been recently recognized by many palaeobiologists as the pitfalls of under-sampled intervals and diversity data, therefore have become a major problem in analyzing diversity patterns during the earth history. In this paper we introduced and reviewed some biases in measuring biodiversities from fossil records using the Ordovician database of marine fossils and the Permian brachiopod database in the Asian-Western Pacific region as examples. The simplest method to count the number of taxa to measure the biodiversity may produce significant biases to distort the diversity pattern due to the different preservation and sampling intensities of various fossils. Palaeobiological biodiversity curves mostly should be corrected using rarefaction when taxonomic lists or occurrences of fossils are available. Most metrics or methods are worth applying although no perfect one removing biases is available yet.

Q91-3

国家杰出青年基金 (No .40 2 2 5 0 0 5 )，创新研究群体资助 ( 4 0 3 2 12 0 2 )，国家重点基础研究发展规划项目 (G2 0 0 0 0 7770 0 )共同资助